Jul 16, 2013 10:04 AM by Stephen Bowers
The Associated Press says scientists have long suspected that large earthquakes can trigger other smaller tremors on thousands of miles away, especially in areas that are volcanically active like Yellowstone National Park.
Researchers now say that oil and gas drilling may make those areas more sensitive to large earthquakes, like the one that shook Japan in 2011.
Less is known about earthquakes that occur on faults that are weakened by activities like drilling, though most of these earthquakes are magnitude-2.0 or weaker and are often not even felt. There has also been increased scrutiny for the process of fracking, which uses high-pressure combinations of water, sand, and chemicals to extract oil. Researchers say this practice can also generate small earthquakes.
Scientists studying the connections between large earthquakes and smaller ones say that the 8.8-magnitude earthquake that struck Chile in 2010 may have caused a series of small earthquakes near Trinidad, Colorado.